Non-thermal plasma discharge in air generates several species, including reactive oxygen and nitrogen species (RONS). If, plasma is generated above a water column, some of these species gets transferred into the water column below generating plasma activated water (PAW), which is known to have several applications. These applications are attributed to the reactive species generated by the plasma discharge. To cater specifically to each application, a complete chemical characterization of plasma discharge in air and PAW is vital, as each of these species have their own unique contribution to the application of PAW. In this work, analysis of the plasma discharge in air using optical emission spectroscopy (OES) and detailed characterization of PAW for its chemical constituents was done. In PAW, the parameters namely, pH, electrical conductivity , , and were quantified as a function of plasma exposure time. The values of ( ) and ( ) obtained in this study were about 50% and 130% higher respectively, than what has generally been reported. The antimicrobial nature of the PAW on Pseudomonas aeruginosa, one of the bacteria responsible for nosocomial infections was also tested, and PAW was able to inactivate the bacterium. Copyright © VBRI Press.